Soft scorpionate coordination at alkali metals

Reported here are the single-crystal X-ray structure analyses of bis-μ-methanol-κ⁴ O:O-bis{[hydrotris(3-phenyl-2- sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl)borato-κ³ H,S,S'](methanol-κO)sodium(I)}, [Na₂ (C₂₇H ₂₂BN₆S₃)₂ (CH₄O) ₄] (NaTm^Ph), bis-μ-methanol-κ⁴ O:O-bis{[hydrotris(3-isopropyl-2-sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl) borato-κ³ H,S,S'](methanol-κO)sodium(I)}-diethyl ether-methanol (1/0.3333/0.0833), [Na₂ (C₁₈H ₂₈BN₆S₃)₂ (CH₄O) ₄] 0.3333C₄H₁₀O 0.0833CH₃OH (NaTm^iPr), and a novel anhydrous form of sodium hydrotris(methylthioimidazolyl)borate, poly[[μ-hydrotris(3-methyl-2- sulfanylidene-2,3-dihydro-1H-1,3-imidazol-1-yl)borato]sodium(I)], [Na(C ₁₂H₁₆BN₆S₃)] ([NaTm^Me] n ). NaTm^iPr and NaTm^Ph have similar dimeric molecular structures with κ³ H,S,S'-bonding, but they differ in that NaTm^Ph is crystallographically centrosymmetric (Z' = 0.5) while NaTm^iPr contains one crystallographically centrosymmetric dimer and one dimer positioned on a general position (Z' = 1.5). [NaTm^Me] _n is a one-dimensional coordination polymer that extends along the a direction and which contains a hitherto unseen side-on η²-C=S-to- Na bond type. An overview of the structural preferences of alkali metal soft scorpionate complexes is presented. This analysis suggests that these thione-based ligands will continue to be a rich source of interesting alkali metal motifs worthy of isolation and characterization.